Hydraulic feeding mechanism for mortising machines



June 15 1926. 1,588,972

l M. MACHACEK HYDRAULIC FEEDING MEGHANISM FOR MORTISING MACHINES Filed April 22, 1925 2 Sheets-Sheet l l y /////////l fa June 15 1926.

1,588,972 M. MACHACEK v HYDRAULIC FEEDING MECHANISM FOR MoR'rIsING MACHINES Filed April 22, 1925 2 Sheen-Sheet 2 Patented June 15, 1926.

UNITED STATES PATENT OFFICE.

MIKE MACHACEK, OF NORTHFIELD, MINNESOTA, ASSIGNOR 0F ONE-FOURTH TO OLIVER MACHACEK, ONE-FOURTH TO GEORGE J. MACHACEK, AND ONE-FOURTH T0 FRANK J. MELOUNECK, ALL 0F NORTHFIELD, MINNESOTA.

HYDRAULIC FEEDING MECHANISM FOR, MORTISIN G MACHINES.

Application filed April 22, 1925. Serial No. 25,009.

My invention relates to improvements in hydraulic actuatinor means for use in connection with the f`eed mechanism of wood working and lother machines, said improvements being particularly well suited for raising and lowering a mortising machine feed table under the various conditions met in practice.

In the use of the conventionally fed mortising machines, it is incumbent upon the operators, in some instances, to lift burdensome loads in the feeding process or to laboriously overcome the action of strong feed retracting devices. In other instances, where such labor is eliminated, the operators have to contend with positive, unyielding feeding means which are incapable of automatically meeting emergencies that often arise and which are practically impossible to adjust finely to any given condition.

It is an object of my invention to provide a simple, durable and relatively inexpensive hydraulic feeding mechanism for lifting a feed table and allowing the same to descend to starting position, said mechanism being adjustable to effect various normal feeding speeds of the feed table and being automatically yieldable, in varying degree, under all adjustments to accord with the resistance, variable or otherwise, that may be met in the mortising operations.

With the foregoing and other objects in view, which will appear in the following description, the invention resides in the novel combination and arrangement of parts and in the details of construction hereinafter described and claimed.

In the drawings, Fig. 1 is a perspective view of a mortising machine equipped with a feeding mechanism embodying my invention, the mortising machine proper, except for the base, being shown in dotted lines, while the base of the machine and said feeding mechanism is shown in solid lines; Fig. 2 is an elevational view, in detail, of the lower forward portion of the structure illustrated in Fig. 1, portions of the ,structural parts being broken away to illustrate interior construction; Fig. 3 is a view similar to Fig. 2, the same illustrating in elevational detail the lower sideportion ofthe structure shown in Fig. 1; Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2 and illustrating particularly the' internal construction of the control valve; Fig. 5 is a detail sectional View taken on the line 5-5 o f Fig. 4 and Fig. 6 is a detail elevational vlew of the automatic tripping mechanism for the control valve.

Reference being had to the drawings, it will be seen that the illustrated embodiment of my invention is associated with a chain-I saw mortising machine of the general conformation of conventional machines of such character. The machine, as shown, includes the usual frame 10, chain cutter 11, countershaft 12, and feed table 13 slidable vertically on said frame 10. Uncommon to the ordinary types of machines of the instant class is the oil reservoir 14 provided in the base 10*l of the frame 10.

The hydraulic feeding mechanism for the feed table 13 includes an hydraulic ram A comprising a cylinder 15, piston 16 in said cylinder and thrust rod 17 rising from said piston through the top vof said cylinder. The upper portion of the thrust rod 17 is threaded and fitted into an internally threaded sleeve 18 journaled at its upper end in a forwardly projecting lug 13a on the feed table 13. Forming a boss for said sleeve 18, beneath said lug 13a, is a bevel gear 19, said gear being meshed with a companion gear 20 on a horizontal shaft 21 journaled in bearings 22 on the feed table 13. A hand-wheel 23 on the horizontal shaft 21 is employed to turn the sleeve 18 through the shaft 21 and gears 19, 20. Said rotation of said sleeve 18 with respect to the thrust shaft 17, which is feathered in the top of the ram cylinder 15 and thus held against turning, provides for setting the feed table 13 higher or lower on the thrust rod 17 as may be required in different m'ortising operations.

On an extension 10b of the base 10HL is a gear pump B of ordinary design, the same having the usual intermeshing gears (not shown) in a gear case 24 for positively propeiling fluid through the pump. The drive shaft 25 of the pump B carries the customary driven pulley 26 and said pulley is connected with a belt 27 to a drive pulley 28 on the counter-shalt 12. Also fitted to the base 10a of the mortising machine. Between the pump B and ram A is a control valve C including an upright cylindrical housing 33 formed with a trunnion 34 socketed in a bearing 35 on the frame 10. Said valve housing 33 is also formed with upper and lower radial ports 36, 37 and with an axial port 38 in the bottom 33a thereof. The control valve C further includes a sleeve valve 39 slidable in said housing 33 and formed with upper and lower diametrical reaches 40. A valve shifter-rod 41, secured in said reaches 40 axially of the sleeve valve 39, rises through a gland 42 in the top 33b of the valve housing 33, said shifter-rod 41 rising to a point near the top of the machine frame 10. Encircling said shifter-rod 41 is an expansion spring 43, the same being interposed between a collar 44 fixed to the rod 41 and a bracket 45 secured to the frame 10 and through which said rod 41 is slidably guided. The action of the spring 43' yieldingly holds the sleeve valve 39 elevated (solid lines, Fig. 4), said sleeve valve being depressed (dotted lines, Fig. 4) against the action of said spring 43 by means of a footlever 46. This foot lever 46 is pivoted mediallv to the shifter-rod 41 and at its rearward end to the frame 10, the forward end of said foot lever being provided with a pedal 46.

Leading from the egress side of the gear case 24 of the pump B is a supply pipe 47, the same extending into the upper port 36 in the valve housing 33. Leading into the reservoir 14 from the supply pipe 47 is a pipe 48 fitted with a fixedly adjustable valve 49 of ordinary type as in the nature of a common glove Valve. Also leading into said reservoir 14 from said supply pipe 47 is an additional pipe 50, the same being tted with a common pressure relief valve 51. Another pipe 52, leading from the lower port 37 in the valve housing 33, empties into the reservoir 14. An ingress-egress pipe 53 communicates at one end through the port 38 with the interior of the valve housing 33 and at theother end thereof with the lower end of the ram cylinder 15 beneath the piston 16 therein.

The pump B, driven from the countershaft 12 of the mortising machine. constantly takes iuid from the reservoir 14 forcing it into the pipe 47, the output of said pump increasing or diminishing according to variations in the speed of rotation imparted to the counter-shaft 12. 1n the absence of pressure on the pedal 46a of the foot lever 46, the spring 43 holds the sleeve valve 39 elevated and in position covering the upper ingress port 36 of the valve-housing 33.

; With said port 36 thus blocked, the Huid under pressure from the pump B is shunted back into the reservoir 14 through the pipes 48, 50, so much thereof returning through the pipe 48 as is permitted by the valve 49 and the remainder returning through the pipe 50 past the relief valve 51.

Downward pressure brought to bear upon the pedal 46a causes the sleeve valve 39 to be depressed against the action of the sprlng 43. With said sleeve valve 39 thus depressed, the upper port 36 in the valve housing 33 is uncovered and the lower port 37 covered, the covering of said latter port 37 being effected prior to the commencement of the uncovering of said former port 36. With the port 36 uncovered, fluid, under pressure from the pump B, is forced through the sleeve valve 39 and ingress-egress pipe 53 into the cylinder 15 of the ram A. Exerting its pressure against the piston 16 of the ram A, the fluid causes the elevation of the feed table 13, whereby the work thereon is fed to the cutter chain 11 above said table. 1t is in effecting this stroke of the table 13 that the advantages of my feeding means are most pronounced. Assume, for example, that very soft wood is being mortised. The highest speed of the table 13 would then be desired and this is had by nearly, if not entirely., closing .the valve 49. Encountering limited or no escape through the pipe 48 to the reservoir 14 and similarly blocked against shunting flow through the pipe 50, due to the absence of substantial resistance against the feed table 13, the oil from the pump B is employed in full volume to operate the ram A. W'ere the table 13 to present a harder stock to the cutter chain 11` a slower feeding speed of said table would` be more desirable and to effect such speed, the valve 49 would be opened slightly to permit the shunting of a limited amount of fluid to the reservoir 14 through the pipe 48. Regardless of the adjustment of the valve 49 in thel shunt pipe 48, the relief valve 51 in the shunt pipe 50 is constantly to be relied upon to permit of the retarding of the feed table 13 under any adjusted normal speed, as upon the encountering by the chain cutter 11 of knots or irregular grains in the work, or the accidental blocking of the feeding movement of said table.

Automatically limiting the elevation of the feed table 13, through the medium of the control valve C, is an adjustable tripstop comprising a collar 54 adjustably clamped by means of a wing-nut 55 on the valve rod- 41 and arranged to be engaged by a trip-lug 56 (Fig. 6) on the back of the feed table 13. Lifted by the shifter-rod 41. through the spring 43 upon the release of the foot lever 46 or by the action of the trip lug 56, the sleeve valve 39 is elevated to cover the ingress port 36 and uncover the drain port 37 in the valve housing 33. Following this disposition of said sleeve valve 39, the fiuid in the ram cylinder 15 is free to return. to the reservoir 14 and 'does so return by force of the ram piston 16 in the fall of the feed table 13. To cushion the impart of the pist-on 16 against the bottom of the cylinder 15 and to keep Vsaid piston from blocking the ingress of oil to the cylinder beneath the piston 16, I interpose a spring 57 at. the bottom of the cylinder 15. said spring being coiled at its lower end about a boss 58 rising from the bottom of said cylinder.

The valve housing 33 is formed with an internal annular groove 33c encircling the sleeve valve 39 and communicating with the ingress port 36. Through this groove 33, fiuid pressure is applied to the sleeve valve 39 annularly thereof with the result that side thrust of the sleeve valve against the valve housing is entirely eliminated.

A seepage drain-pipe 59 leading from the top of the ram cylinder 15 to the reservoir 14 returns to the latter any oil that may accumulate above the piston 16 in objectionable quantity. And said reservoir is fitted with a breather ipe 60 to maintain atmospheric pressure t erein.

From the foregoing it will be understood that an operator has only to adjust the shunt valve 49 to secure the desired and most effective normal fee-ding speed of the feed table 13; that by simply operating the easily depressed foot lever 46, the feed table 13 will be caused to rise and carry the work into the cutter chain 11; that the relief or shunt valve 51 will automatically compe-nsate for overestimation of the proper feeding speed of the table 13, also for the retardation or cessation of movement of said table as by resistance against continued feeding movement thereof and, further, that said feeding table will quickly return to starting position Vupon the voluntary release of the foot lever 46 or upon the elevation of said footlever by the action of the adjustable trip device (Fig. 6) associated with the sleeve valve shifter-rod 41.

Changes in the specific form of my invention, as herein disclosed, may be made Within the scope of what is claimed Without departing from the spirit of my invention.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. The combination with a machine including a frame, a vertically slidable feed table thereon and a fluid reservoir in said frame, of a ram including a cylinder, a piston therein and a thrust rod rising from said piston for lifting said feed table, a fluid pressure pump fe'd from said reservoir, a control valve comprising an upright cylindrical housing and a sleeve valve slidable therein, said housing having a radial ingress port and a radial egress port therein,- the former above the latter and also having -an axial egress-ingress port at the bottom thereof, a fluid supply pipe leading from the pump to said upper rt, a shunt pipe lea-ding from said supp y pipe to said reservoir, a fixedly adjustable valve fitted in said ipe, a second shunt pipe leading from sai supply pipe to said reservoir, a yielding re ief valve fitted in said second shunt pipe, a combined port and cover said lower port, whereby said ram cylinder is brought into communication with said upper port, a valve actuating rod rising from said sleeve valve, a spring acting on said rod to yieldingly hold the sleeve elevated, a lever connected with said rod for depressing the valve sleeve against the action of said spring, an adjustable stop on the rod, and an abutment on the feed table beneath said stop, said abutment being adapted to co-operate with said stop to lift the valve sleeve against the action of said pedal.

2. The combination with a machine including a frame. and a feed table slidablevertically on said frame, of a ram including a cylinder', a piston therein and a thrust rod rising from said piston for lifting said feed table, a fluid reservoir, a fluid pressure pump fed from said reservoir, a control valve .comprising an upright cylindrical housing and a sleeve valve slidable therein, said housing having a radial ingress port and a radial egress porttherein. the former above the latter and also having an axial egress-ingress port at the bottom thereof, a fluid supply pipe leading from the pump to said upper port, a valved shunt pipe leading from said supply pipe to said reservoir, a combined feed and drain pipe extending from the axial port in the valve housing to the ram cylinder, said sleeve valve, at elevated position, being adapted to cover the upper radial port and uncover the lower radial port, whereby the ram cylinder is brought into communication with said latter port and, in depressed position, to uncover said upper port and cover said lower port, whereby said ram cylinder is brought into communication with said upper port, and means for shifting the sleeve valve in said valve housing.

3. The combination with a machine including a frame and a feed table movable thereon, of a ram including a cylinder, a piston therein and a piston rod for propelling said feed table, a fluid pressure pump, a control valve comprising a cylindrical housing and a sleeve valve slidable therein, said housing having a radial ingress port, a radial egress port therein and an axial e essingress port at one end thereof, said dironsing also having an internal annular groove therein lcommunicating with said ingress port, a fluid supply pipe leading from the pump-to said ingress port, said pipe having a valved fluid outlet therein, a combined feed and drain pipe extending from the axial port in the valve housing to the ram cylinder, said sleeve valve, in one position, being adapted to cover the ingress port and uncover the egress port whereby the ram cylinder is brought into communication with said latter port and, in another position, to uncover said ingress port and cover said egress port, whereby said ram cylinder is brought into communication with said ingress port, and means for shifting the sleeve valve in the valve housing.

4. The combination with a movable feed member, of a fluid operated ram associated therewith for actuating the same, a source of supply for fluid under pressure, a control valve including a valve housing and valve head movable therein. meansifor shi fting said valve head in said housing, a fluid supply pipe leading from said source of supply to said housing, a valved outlet associated with said pipe, a combination feed and drain pipe connecting said housing and ram, said housing having an egress port therein and said valve head a-dapted alternately to obstruct the ingress of fluid to the housing through the feed pipe and the escape of fluid from the housing through said egress port, and adjustable means associated with said movable feed member for shifting said valve head into position arresting the ingress of fluid to the valve housing from said feed pipe and providing for the egress from said port of fluid draining into said housing from said ram.

5. The combination with a movable feed member, of a fluid operated ram associated therewith for actuating the same, means for supplying fluid under pressure, a control valve including a valve housing and'valve head movable therein, means for shifting said valve head in said housing, a, fluid supply pipe leading to said housmg, a valved outlet associated with said pipe, a combination feed and drain pipe connecting said housing and ram, said housing having an egress ort therein and said valve head adapte alternately to obstruct the ingress of fluid to the housing through the feed pipe and the" escape of fluid from the housing through said egress port.

6. The combination with a movable feed member, of a fluid operated ram associated therewith for actuating the same, means for supplying fluid under pressure, a supply conduitfor such fluid leading to said ram, said conduit having a valved outlet therein, an outlet conduit associated with said supply conduit for draining the ram, and a control valve common to the supply conduit and to said drain conduit, said control valve being adapted to obstruct and clear said conduits, the obstruction of one being attended with the clearing of the other.

7 The combination with a movable feed member, of means for supplying fluid under pressure, a supply pipefor such fluid, a valved outlet communicating with said supply` a fluid operated ram associated with said feed member foi actuating the same, means for the ingress of fluid from the supply pipe to said ram and for the egress of fluid from the ram, and fluid cont-rol mechanism associated with said means for alternately supplying fluid to the ram and permitting of the escape thereof from said ram.

In testimony whereof, I have signed my name to this specification.

MIKE MAGHACEK. 

